The present invention relates to new platinum (II) complexes.
Heretofore, many reports have been made about platinum (II) complexes and the anti-tumor activity thereof, e.g. [Chem. Biol. Interaction, vol. 5, 415-424 (1972), Bioinorg. Chem. vol. 2, 187-210 (1973), Res. Commun. Chem. Pathol. Pharmacol. vol. 7, 529-538, etc.]. The present inventors, while studying cis-platinum (II) complexes of 1,2-diamino-cyclohexane (hereinafter referred to as "dac"), succeeded to resolve dac, which is used as a starting compound, into three isomers, i.e., cis-, trans-l- and trans-d-; synthesized cis-platinum (II) complexes using these isomers and found that these complexes have anti-tumor activity. These complexes, their synthesis and utility are disclosed in U.S. patent application Ser. No. 775,216 filed on Mar. 7, 1977 now abandoned.
It has now been found that various other cis-platinum (II) complexes may be synthesized using the three isomers of dac as a starting compound; and these complexes exhibit strong anti-tumor activity.